Not so stock fuel injetctor feedback

Brian Link brianl at
Mon Nov 11 11:03:00 EST 2002


I managed to put in the SD 36# injectors in my car over the weekend.  I
drove the car a bunch and then tested mixture on my wideband O2 sensor.
Has anyone else on this list installed injectors with increased flow on
software that was configured to run on stock injectors?  Here are my
results, With the wideband connected in place of my O2 sensor all my
testing was looking at the flow from the fuel mapping not closed loop.
At part throttle up to about 10psi the car was near stoch ~14.2 - 14.4 :
1.  At full throttle and full boost up to 24 psi things were at 12.4:1
for most of the time but got slightly richer the closer to redline.

With my O2 sensor back in place, and using the autometer A/F gauge
things appear exactly the same before except the car goes into open loop
mode more quickly. Throttle response feels stronger because of this.

Oddly enough my fuel economy stayed the same or got a little better.  A
120 mile round trip to the airport reported a 27.7 mpg?  Do any of you
have a BTDT with larger injectors?

The injectors seem to work fine, and the car feels stronger.  I plan on
doing a few dyno runs next week to see if I am delusional.

Brian Link
Boulder, CO

More information about the 200q20v mailing list